Sulfonyl and sulfinyl phenyl ureas

ABSTRACT

Compound of the formula   WHEREIN R1 is hydrogen or alkyl of 1 to 4 carbon atoms, R2 is alkyl of one to four carbon atoms, R3 is hydrogen or alkyl of one to four carbon atoms, X and Y are hydrogen, halogen of atomic number nine to 35, alkyl of one to four carbon atoms or alkoxy of one to four carbon atoms and m is one or two. The compounds are herbicides.

United States Patent Brown, deceased SULFONYL AND SULFINYL PHENYL UREASInventor: Melancthon Starr Brown, late of Berkeley, Calif. by Gustave K.Kohn, administrator Assignee: Chevron Research Company, San

Francisco, Calif.

Filed: Nov. 9, 1970 Appl. No.: 88,213

U.S. c1. ..260/553 A, 71/120 Int. Cl ....'.C07c 127/18 Field'of Search..260/553 A References Cited UNITED STATES PATENTS Martin et al...260/553 A [451 Dec. 26, 1972 Primary Examiner-LeoniZitver AssistantExaminer-Michael W. Glynn Attorney-G. F. Magdebur'geg john Stoner, Jr

J. A; Bucharianjrfand kaymond Owyang wherein R is hydrogen or alkyl of 1to 4 carbon atoms, R isalkyl of one to four carbon atoms, R is hydrogenor alkyl of one to four carbon atoms, X and Y are hydrogen, halogen ofatomic number nine to 35, alkyl of one to four carbon atoms or alkoxy ofone to four carbon atoms and m is one or two. The compounds areherbicides.

7 Claims, No Drawings SULFONYL AND SULFINYL PHENYL UREAS BACKGROUND OFTHE INVENTION 1. Field I The present invention is related to substitutedureas which are useful as herbicides. More particularly, the presentinvention is directed to arylsulfinylaryl ureas and arylsulfonylarylureas. I

2. Prior Art N-substituted ureas have found use in a variety ofcommercial applications dependingupon the nature and number of theN-substituents. Thus, for example, N,N-dialkyl-N-4-(phenoxy) and(phenylthio)phenyl ureas and related ureas are disclosed in US. Pat. No.3,060,235 as herbicides. Also N,N-alkyl-N'-alkyl-sulfonyl andsulfinylphenyl ureas and related compounds are disclosed in US. Pat. No.3,326,663, as being useful herbicides.

SUMMARY OF THE INVENTION It has now been found thatN,N-dialkyl-N-4-(arylsulfinyl or sulfonyl)aryl ureas of the formulaatoms, R is alkyl of one tofour carbon atoms, R is hydrogen oralkyl ofone to four carbon atoms, X and Y are hydrogemhalogen of atomic numbernine to 35, alkyl of one to four carbon atoms or alkoxy of one'to fourcarbon atoms and m is one or two are .excellent herbicides and in manyapplications are unexpectedly superior to the prior art compounds.

DESCRIPTION OF THE INVENTION wherein R -is hydrogen or alkyl of one tofourcarbon atoms, preferably methoxy. Y is preferably in the paraposition.

The halogen substituents of the compounds'of the present invention arepreferably chlorine or fluorine.

Examples of radicals which R and R may represent are methyl, ethyl,'n-propyl, isopropyl, n-butyl and isobutyl. f

Representative radicals which R may represent are hydrogen, methyl,ethyl, n-propyL-isopropyl, n-butyl and isobutyl.

Typical radicals which X-and Y may represent are hydrogen, fluorine,chlorine, bromine, methyl, ethyl, n-

propyl, isopropyl, n-butyl, isobutyl, methoxy, ethoxy,

' N-methyl-N-ethyl-N-3-ethoxy-4-(o-chlorophenylsul- The compounds of thepresent invention may be represented by the following formula I o Inwherein R is hydrogen or alkyl of one to four carbon atoms, R is alkylof one to four carbon atoms, R is hydrogen or alkyl of one to fourcarbon atoms, X and Y are hydrogen, halogen of atomic. number 9 to 35(fluorine, chlorine or bromine), alkyl individually of one to fourcarbon atoms or alkoxy individually of one to four carbon atoms (X and Ymay be the same or different), and m is l or 2.

Preferably the compounds of the present invention may be represented bythe above formula wherein R is hydrogen or alkyl of one to two carbonatoms, preferably hydrogen or methyl, R is alkyl of one to two carbonatoms, preferably methyl, R is hydrogen or alkyl of one to two carbonatoms, preferably hydrogen or methyl, Y is hydrogen, halogen of atomicnumber nine to 35 or alkyl of one to four carbon atoms, preferablymethyl,.X is hydrogen, halogen of atomic number nine to 35, alkyl of oneto four carbon atoms preferably methyl, or alkoxy of one to four carbonfonyl )phenyl urea.

The ureas of the present invention may be prepared as follows. v

The initial urea intermediate is most conveniently made by adding theappropriate phenylor substitutedphenyl isocyanate to a dialkylamine,such as dimethylamine, in a relatively non-polar solvent, such asbenzene or toluene. Thereaction may be written as A temperature of2550C. usually is sufficient, but

.temperature up to reflux may be used. Alternately, the

amine may be added to the isocyanate. The insoluble urea product isisolated by filtration and generally is pure enough to be used withoutfurther purification.

In the event that the desired isocyanate is not available, the ureaintermediate can be made from a suitable substituted aniline and adialkyl carbamyl chloride, using a basic acceptor, such astriethylamine. Thus:

X a... M

' reaction may be'written-as The N,N-dialltyl-N'-phenyl"or .substituted:phenyl urea, in a solvent which at least partially dissolves the ureaintermediate, isthen reacted with an appropriate sulfenylchlor ide, suchas phenylsulfenyl chloride or pchlorophenylsulfenylchloride. Di-methylformamide is suitable as a solvenLA' tertiary amine, such aspyridine or triethylamine, may be used as a basic acceptor. The

The reactionis carried out at temp ratures in theran'ge of C. to 50C.,preferably '2030C.' Reactions usually require from 0.5 to l hours tocomplete. When the reactants are mixed at low temperatures, the reaction is usually completed at high'temperatures. Dilution of theproduct-solution with water results in precipita tion of the product,which may be filtered and washed with water to remoye' any amine.hydrochloride..'lhe product may be-purified byflrecrystallization froman aromatic hydrocarbon or acetonitrile.

The'oxidation-of the sulfide to a sulfoxide or to a sul-' Severalmethods are available for carrying out this conversion,'such asoxidation by nitric acid, potassium permanganate, potassium dichromate,etc.; but the preferred'method is by'peroxidic oxidation. Oxidizers forthis reaction include hydrogen peroxide, peracetic acid, perbenzoicacid, etc. m-Chloroperbenzoic acid is preferred. Netherlands Pat. No.65/12259 teaches the pe'rbenzoic acid oxidation of sulfides.

' The sulfides are oxidized to sulfoxides or sulfones by adding 1 or 2moles, respectively, of oxidizing agent to the sulfide in a suitablesolvent. m-Chloroperbenzoic acid in chloroform or hydrogen peroxide inglacial acetica'cid may be used to effect these oxidations. Theoxidations are usually carried out at temperatures in the range of 0C.to 50C. Low temperatures are preferred. Upon completion of the reaction,the reactants no longer give a positive potassium iodide test. Theproduct is a solid material, which may be recovered by filtration andpurified by crystallization from asolventsuch as acetonitrile.

"Also see U.S. Pat..No. 3,060,235 for disclosure as to' the preparation'of certain N,N-dialkyl-N' phenylthiophenyl'ureas.

the following examples. EXAMPLE '1 N ,N-'di me thyl N-m-chlorophenyla..-

1 'Eighteen g; (0.4 mole) 'of dimethylaminewas added gradually to 50 g.(0.33- mole) of m-chlorophenylisow The preparationof the compounds ofthe presentinvention is illustrated more particularly by reference tocyanate in 500 cc benzene, cooling slightly to maintain a temperature ofabout 30C. The mixture was allowed to stir overnight at roomtemperature. The product was collected'on a Buchner funnel, washed withbenzene, and dried. The :62 g. of product, which meltedat l44l47C.,represents a percent yield.

EXAMPLE 2 N,N-dimethyl-N-3-methyl-4-(4- chlorophenylt hio)phenyl ureaTwenty g. of N,N -dimethyl-N -m-tolylurea and 10 ml. pyridinewerecombined in ml. dimethylforma mide and stirred in an ice bath while22 of pchlorophenylsulfenyl chloride was added slowly. After beingstirred one hour at room temperature, the reac tion mixture was addedto-750 ml. of ice and water plus a little mixed hexane. The solidproduct was collected on a Buchner funnel, washed with'water and hexane,then recrystallized from acetonitrile. There 1 wasrecovered 36 g. ofproduct melting at l 65 -168C., which represents 64 percent yield. Theanalysis was:

Found Calculated S 10.00 9.74 Cl I 1.39

EXAMPLE 3 -'N,N-dimethyl-N-3-methyl-4-(4- chloro-phenylsulfinyl)phenylurea the residual crude product was purified by recrystallization fromacetonitrile. There was recovered 6.3 g. of solid, which melted atl6817lC. and analyzed as follows:

Calculated I Found S 9.49 9.52 CI 10.53 10.48

EXAMPLE4 7 N,N-dimethyl-N 3 methyl-4-(4- chloro -phenylsulfonyl)phenylurea Eight g. of

was stirred as' 10.5 g. m-chloroperbenzoic acid was added in incrementswith a slight exothermicity. The

reaction mixture was stirred overnight at room tem-N,N-dimethylI-N'--3-methyl-4 (4- chlorophenylthio)phenyl urea in 250 ccchloroform perature. It was then washed with saturated aqueousCalculated Found s 9.07 8.86 Cl 10.05 10. 19

Other compounds of the present invention were prepared in similarfashion to the above examples and are tabulated in Table l.

TABLE I Element Analysis----% 7 S C1 Melting Compound calc.- found calc.found Point C. N,N-dimethyI-N'-4-(pchlorophenylsulfinyl) phenyl ureaN,N-din1ethyl-N'-4-(pchlorophenylsulfonyl) phenyl ureaN,N-dimethyl-N'-3- methyl-4-(p-tolylsulfinyl)phenyl ureaN.N-dimethyl-N-3- methyl-4-(p-tolylsulfonyl)phenyl urea 1N,N-dimethyl-N'-3- methyl-4-(phenylsulfinyl) phenyl ureaN,N-dimethy1-N'3- methyl-4-(phenylsulfonyl)phenyl urea N,Ndimethyl-N-3-methoxy-4-(pchlorophenylsulfinyDphenyl urea N,N-dimethyl-N'-3-methoxy-4-(p-chlorophenylsulfonyl)phenyl urea N,N-dimethyl-N'-3--chloro4-(p-chlorophenylsulfonyl)phenyl urea N-methyl-N'-methyl-N'-4-(p-chlorophenylsulfonyl)phenyl urea N-methy1-N'-methylN'-2-fluoro-4- (p-chlorophenylsulfonyl)phenyl urea 9.00 9.94;l0.28l10-1l4 nitrogen UTILITY and seedlings. For post-emergenceapplications the Preand post-emergence herbicidal tests onrepresentative ureas of this invention were made using the followingmethods:

PRE-EMERGENCE TEST An acetone solution of the test ureas. was preparedby mixing 750 mg. urea, 220 mg.- of a nonionic surfactant and 25 ml.ofacetone.- This solution was added to approximately 125 ml. of water,containing 156 mg. of

surfactant.

Seeds of the test vegetation were planted in a pot of soil and the ureasolution was sprayed uniformly onto the soil surface at a-dose of 100micrograms per cm The pot was watered and placed in a greenhouse at atemperature of about 80-85F. The pot was watered intermittently and wasobserved for-seedling emergence, health of emerging seedlings, etc. fora 3-week period. At the endof'this period the herbicidal effectivenessof the urea was rated based onthe physiological i observations. A 0 'to100 scale was used; 0 representing no phytotoxicity, 100 representingcomplete kill.

POST-EMERGENCE TEST The test urea was formulated in the same manner as 1described above for the pre-emergence test. The conureas of the presentinvention will be applied directly to centration of the urea in thisformulation was 5000 ppm. This formulation was uniformly sprayed on thepot containing 24-day-old plants (approximately 15 to 25 plants per pot)at a dose of 100 micrograms per cm. The pots were then placed in agreenhouse at a temperature of 85F. and then watered intermittentlyattheir bases as needed. The plants were observed periodically forphytotoxic effects and physiological and morphological responses to thetreatment. After 3 weeks the herbicidal effectiveness of the urea wasrated based on these observations. A 0 to 100 scale was used; I

0 representing no phytotoxicity, 100 representing complete kill.

The'results of these testsappear in Table II.

TABLE II Herbicidal Effectiveness Pre/Post CompoundO W C M P LN,N-dimethyl-N'-4- (p-chlorophenylsulfinyl) phenyl urea 99/ 100/ 100/100/'100/100 100/100 100 100 100 100 N,N-dimethyl-N'-4-(p-chlorophenylsulfonyl) phenyl urea 99/ 96/ 100/ 100/ 100/100 100/100100 100 N,N-dimethyl -N-3- methyl-4-(p-chlorophenylsulfinyl)phenyl urea78/ 78/ 99/ 100/ 100/100 100/100 100 100 100 I00 N,N-dimethyl-N'-3--methyl-4 phenylsulfonyl)phenyl urea 1 90/100 100100! 100 100/100100/100 60 100 60 100 N,N-dimethyl-N'-3-methyl-4-(p-tolylsulfinyl)phenyl urea /90 60/ 78/ 100/ 100/100 100/10090 90 I00 N,N-dimethy1-N'-3-' methyl-4-(p-tolylsulfonyl) phenylurea-100/ 60/ 100/ 100/100 100/ 100/100 N.N-'dimethyl-N-3-methyl-4-(phenylphenyl urea N,N-dimethyl-N'.-3- methyl-4-(phenyl- Isulfonyl) phenyl urea t 96/ 100/ 100/ /100 100/100 -l00. l 00100N,N-dimethyl-N'-3- 3 methoxy-4-(pchlorophenylsulfinyl )phenyl I 78/100-methoxy'-4-(pchlorophenyli I sulfinyhphenyl urea N.N-di'mcthyl-'N"-3"/l60/ 78/96 100/ 100/1 00 methoxy-4-( p-chloro 100 Y 100 v 7 s 47 s155;- 100/ 1 0 100 100/1'00 O Wild Oats (Avgnafama):

W Watergrass (Echinochlod crusgalli) C Crabgrass (Digimria sanguinalis)M Mustard (Braxsica arvensis) L Lambsquarter (C henopodium albuni)Compoundsof the present invention are, in general,

significantly [superior to the phenylthiophenyl urea compounds of theprior art. Thus, for example, the many: compounds of the presentinvention are significantly more effective as preand post-emergenceherbicides at lower application concentrations than related compounds ofthe .prior art. Thus using the procedures of the above tests, but usingsmaller dosages, .the following representative results were obtained asshown in Table Ill.

' p-chlorophenylthio) chlorophenylthio)phenyl urea (Comparison compound)TABLE 111(0 Post ,Conc. Compound meglcm I r 33 .72 100-100* methyl-A- I(p-chlorophenylsulfinyl)phenylurea N,N-dimethyl-N 33' 88 -93".3-methyl-4- (p-chlorophenylsulfonyl)phenyl urea N,N-dimethyl-N' 33 j-40 .17 33* 3-me'thyl-4-, (p-chlorophenylithio)phenyl urea (Comparisoncompound) g N,N-dimethyl-N'- 33 100 100 3-methyl-4- (ply s fi yh' phenylurea N,N-dimethy1-N-' 33 95 67 3-methy1-4- (p-tolylsulfonyl) phenylurea"N,N-dimethyl-N' 33 13 3 0 88 50 -3-methyl-4- g (p-tolylthio) phenyl urea(Comparison compound)- The amount of the urea administered will varywith the particular plant part or. plant growth medium which i is to becontacted, the general location'of application, i.e., sheltered areassuch .a's-greenhouses as compared to exposed areas such as field, aswell as the desired type vof control. For pre-emergent control of mostplants dosages in the range of about 0.5 to 20 lbs. per acre willbe-used. Such administration will give a concentration .of about 2 to 80ppm. ure'a distributed throughout 0.1 acre-foot. For post-emergenceapplication, such as foliar spray application, compositions containingabout 0.5 to 8 lbs. urea per 100 gal. spray will be used.'Suchapplication is equivalent to about 0.5 to 20 lbs. urea per acre.

' The herbicidal compositions of this invention comprise a herbicidalamount of one or more of the above described ureas intimately admixedwith a biologically inert carrier. The carrier may be a liquid diluentsuch as water or acetone or a solid. The solid may be in the form ofdust powder or granules. These compositions will also usually containadjuvants such as a wetting or dispersing agent to facilitate theirpenetration into the plant growth media or plant tissue and generallyenhance theireffectiveness. These compositions may also contain otherpesticides, stabilizers, conditioners,

fillers and the like..'

. As will be evident to those skilled in the art, various modificationson this invention can be made or ,followed, in the light of theforegoing disclosure anddiscussion, without departing from the spirit orscope ,of. the disclosure or from the scope of the following claims.

What is claimed is: 1, A compound of the formula wherein alkyl of one tofour carbon atoms, R is alkyl of one to four carbon atoms R is methyl, Ris methyl and R is hydrogen or methyl.

4. A compound of claim 2 wherein X is hydrogen, halogen of atomic numbernine to 35, alkyl of 1 to 4 carbon atoms, or alkoxy of one to fourcarbon atoms and Y is hydrogen, halogen of atomic number nine to 35, oralkyl of one to four carbon atoms.

5 A compound of claim 1 wherein the halogens are of atomic number 9 to17.

6. A compound of claim 1 wherein R is hydrogen or methyl, R is methyl, Ris hydrogen or methyl, X and Y are hydrogen, fluorine, chlorine, methylor methoxy.

7. A compound of-claim 6 wherein m' is l, R and R are methyl, R and Xare hydrogen, and R is p.-chl0ro.

2. A compound of claim 1 wherein R1 is hydrogen or alkyl of one to two carbon atoms, R2 is alkyl of one to two carbon atoms and R3 is hydrogen or alkyl of one to two carbon atoms.
 3. A compound of claim 1 wherein R1 is hydrogen or methyl, R2 is methyl and R3 is hydrogen or methyl.
 4. A compound of claim 2 wherein X is hydrogen, halogen of atomic number nine to 35, alkyl of 1 to 4 carbon atoms, or alkoxy of one to four carbon atoms and Y is hydrogen, halogen of atomic number nine to 35, or alkyl of one to four carbon atoms.
 5. A compound of claim 1 wherein the halogens are of atomic number 9 to
 17. 6. A compound of claim 1 wherein R1 is hydrogen or methyl, R2 is methyl, R3 is hydrogen or methyl, X and Y are hydrogen, fluorine, chlorine, methyl or methoxy.
 7. A compound of claim 6 wherein m is 1, R1 and R2 are methyl, R3 and X are hydrogen, and R4 is p-chloro. 